Adolescence is a period of rapid growth and physical change; a central question is whether consuming alcohol during this stage can disrupt development in ways that have long-term consequences. In general, the existing evidence suggests that adolescents rarely exhibit the more severe chronic disorders associated with alcohol dependence such as liver cirrhosis, hepatitis, gastritis, and pancreatitis. Adolescents who drink heavily, however, may experience some adverse effects on the liver, bone, growth, and endocrine development. Evidence also is mounting, at least in animal models, that early alcohol use may have detrimental effects on the developing brain, perhaps leading to problems with cognition later in life. This article summarizes the physiological effects of alcohol on adolescents, including a look at the long-term behavioral and physiological consequences of early drinking.
KEY WORDS: underage drinking; binge drinking; AODU (alcohol and other drug use); adolescence; growth and development; puberty; physiological AODE (alcohol and other drug effects); psychological AODE; chronic AODE; brain; liver; bone; reproductive system; sexual maturation; long-term AOD (alcohol and other drug) use; animal studies
The damage that long-term heavy alcohol consumption can do to the health of adults is well documented. Some research suggests that, even over the shorter time frame of adolescence, drinking alcohol can harm the liver, bones, endocrine system, and brain, and interfere with growth. Adolescence is a period of rapid growth and physical change; a central question is whether consuming alcohol during this stage can disrupt development in ways that have long-term consequences.
Liver disease is a common consequence of heavy drinking. More severe alcohol-related liver disease typically reflects years of heavy alcohol use. However, elevated liver enzymes that are markers of harm have been found in adolescents with alcohol use disorders and in overweight adolescents who consume more modest amounts of alcohol.
During puberty, accelerating cascades of growth factors and sex hormones set off sexual maturation, growth in stature and muscle mass, and bone development. Studies in humans have found that alcohol can lower the levels of growth and sex hormones in both adolescent boys and girls. In animals, alcohol has been found to disrupt the interaction between the brain, the pituitary gland (which regulates secretion of sex hormones), and the ovaries, as well as systems within the ovaries that are involved in regulating sex hormones. In adolescent male animals, both short- and longterm alcohol administration suppresses testosterone; alcohol use also alters growth hormone levels, the effects of which differ with age.
Studies on alcohol and adolescent bone development are limited. In studies of male and female rats, chronic alcohol consumption (an alcohol diet) for the length of adolescence was found to stunt limb growth. One study found that feeding female rats alcohol in a way that mimics binge drinking resulted in either increases in bone length and density or in no change with more frequent bingeing. In human adolescent males but not females, studies have found that alcohol consumption decreases bone density.
The brain also is changing during adolescence. Adolescents tend to drink larger quantities on each drinking occasion than adults; this may in part be because adolescents are less sensitive to some of the unpleasant effects of intoxication. However, research suggests that adolescents may be more sensitive to some of alcohol's harmful effects on brain function. Studies in rats found that alcohol impairs the ability of adolescent animals more than adult animals to learn a task that requires spatial memory. Research also suggests a mechanism for this effect; in adolescents more than adults, alcohol inhibits the process in which, with repeated experience, nerve impulses travel more easily across the gap between nerve cells (i. …